Transcatheter aortic valve implantation: impact on clinical and valve-related outcomes

Transcatheter aortic valve implantation: first results from a multi-centre real-world registry

AIMS

Treatment of elderly symptomatic patients with severe aortic stenosis and co-morbidities is challenging. Transcatheter aortic valve interventions [balloon valvuloplasty and transcatheter aortic valve implantation (TAVI)] are evolving as alternative treatment options to surgical valve replacement. We report the first results of the prospective multi-centre German Transcatheter Aortic Valve Interventions-Registry.

METHODS AND RESULTS

Between January 2009 and December 2009, a total of 697 patients (81.4 ± 6.3 years, 44.2% males, and logistic EuroScore 20.5 ± 13.2%) underwent TAVI. Pre-operative aortic valve area was 0.6 ± 0.2 cm² with a mean transvalvular gradient of 48.7 ± 17.2 mmHg. Transcatheter aortic valve implantation was performed percutaneously in the majority of patients [666 (95.6%)]. Only 31 (4.4%) procedures were done surgically: 26 (3.7%) transapically and 5 (0.7%) transaortically. The Medtronic CoreValve™ prosthesis was used in 84.4%, whereas the Sapien Edwards™ prosthesis was used in the remaining cases. Technical success was achieved in 98.4% with a post-operative mean transaortic pressure gradient of 5.4 ± 6.2 mmHg. Any residual aortic regurgitation was observed in 72.4% of patients, with a significant aortic insufficiency (≥Grade III) in only 16 patients (2.3%). Complications included pericardial tamponade in 1.8% and stroke in 2.8% of patients. Permanent pacemaker implantation after TAVI became necessary in 39.3% of patients. In-hospital death rate was 8.2%, and the 30-day death rate 12.4%.

CONCLUSION

In this real-world registry of high-risk patients with aortic stenosis, TAVI had a high success rate and was associated with moderate in-hospital complications. However, careful patient selection and continued hospital selection seem crucial to maintain these results.

Transcatheter aortic valve implantation: early results of the FRANCE (FRench Aortic National CoreValve and Edwards) registry

AIMS

Transcatheter aortic valve implantation is a therapeutic alternative for high-surgical-risk patients with severe symptomatic aortic stenosis. Two models of prosthesis are currently commercialized in France, which can be implanted either via a transarterial or a transapical approach. The aim of the study was to evaluate in a national French registry the early safety and efficacy of transcatheter aortic valve replacement (AVR) using either the Edwards SAPIEN™ or CoreValve™ in high-surgical-risk patients with severe aortic stenosis.

METHODS AND RESULTS

The multicentre national registry was conducted in 16 centres between February 2009 and June 2009, under the authority of the French Societies of Cardiology and Thoracic and Cardio-Vascular Surgery. The primary endpoint was mortality at 1 month. Two hundred and forty-four high-surgical-risk patients (logistic EuroSCORE ≥20%, STS ≥10%, or contra-indication to AVR) were enrolled. Mean age was 82 ± 7 years and 43.9% were female. Edwards SAPIEN and CoreValve were implanted in 68 and 32% of patients, respectively. The approaches used were transarterial (transfemoral: 66%; subclavian: 5%) or transapical in 29%. Device success rate was 98.3% and 30-day mortality was 12.7%. Severe complications included stroke (3.6%), tamponade (2%), acute coronary occlusion (1.2%), and vascular complications (7.3%). Pacemaker was required in 11.8%. At 1 month, 88% of patients were in NYHA class II or less.

CONCLUSION

This prospective registry reflects the real-life experience of transcatheter aortic valve implantation in high-risk elderly patients in France. The early results are satisfactory in terms of feasibility, short-term haemodynamic and functional improvement, and safety. Longer term follow-up will be further assessed.

Transcatheter aortic valve implantation: durability of clinical and hemodynamic outcomes beyond 3 years in a large patient cohort

BACKGROUND

Although short- and medium-term outcomes after transcatheter aortic valve implantation are encouraging, long-term data on valve function and clinical outcomes are limited.

METHODS AND RESULTS

Consecutive high-risk patients who had been declined as surgical candidates because of comorbidities but who underwent successful transcatheter aortic valve implantation with a balloon-expandable valve between January 2005 and December 2006 and survived past 30 days were assessed. Clinical, echocardiographic, and computed tomographic follow-up examinations were performed. Seventy patients who underwent successful procedures and survived longer than 30 days were evaluated at a minimum follow-up of 3 years. At a median follow-up of 3.7 years (interquartile range 3.4 to 4.3 years), survival was 57%. Survival at 1, 2, and 3 years was 81%, 74%, and 61%, respectively. Freedom from reoperation was 98.5% (1 patient with endocarditis). During this early procedural experience, 11 patients died within 30 days, and 8 procedures were unsuccessful. When these patients were included, overall survival was 51%. Transaortic pressure gradients increased from 10.0 mm Hg (interquartile range 8.0 to 12.0 mm Hg) immediately after the procedure to 12.1 mm Hg (interquartile range 8.6 to 16.0 mm Hg) after 3 years (P=0.03). Bioprosthetic valve area decreased from a mean of 1.7±0.4 cm(2) after the procedure to 1.4±0.3 cm(2) after 3 years (P<0.01). Aortic incompetence after implantation was trivial or mild in 84% of cases and remained unchanged or improved over time. There were no cases of structural valvular deterioration, stent fracture, deformation, or valve migration.

CONCLUSIONS

Transcatheter aortic valve implantation demonstrates good medium- to long-term durability and preserved hemodynamic function, with no evidence of structural failure. The procedure appears to offer an adequate and lasting resolution of aortic stenosis in selected patients.

Frequency of conduction disturbances after transcatheter implantation of an Edwards Sapien aortic valve prosthesis

We evaluated the incidence of conduction abnormalities and requirement for permanent pacemaker in patients undergoing transcatheter aortic valve implantation (TAVI) with the Edwards Sapien prosthesis. In 2009, >8,000 patients were treated with TAVI using 1 of the 2 commercialized models of bioprosthesis (Edwards Sapien, Edwards Lifesciences, Irvine, California; and CoreValve, Medtronic, Irvine, California). Occurrence of conduction abnormalities including complete atrioventricular block requiring permanent pacemaker has been reported after TAVI with the 2 models of valve, more frequently with the CoreValve. We analyzed standard 12-lead electrocardiograms of 69 consecutive patients in whom an Edwards Sapien prosthesis was successfully implanted. Electrocardiograms were examined before treatment, at day 1, and at 1-month follow-up. Heart rate, PR and QT intervals and QRS duration were measured and the presence of a first-, second-, or third-degree atrioventricular block was documented. There was a slight increase in heart rate and a discrete decrease in QT interval at day 1. These values had returned to baseline values at 1 month. There was no change in PR interval but a transitory increase in QRS duration was noted. Frequency of left bundle branch block increased from 14.5% at baseline to 27.5% at day 1 with a decreased incidence at day 30 (21.3%). Permanent pacemaker was required in only 3 patients (4.3%). In conclusion, in our experience, conductive disorders and requirement of a definitive pacemaker after implantation of an Edwards Sapien aortic bioprosthesis are infrequent. The physical properties of this prosthesis may explain this observation.

Aortic stenosis: An update

Aortic stenosis (AS) is the most common valvular heart disease in the world. It is a disease of the elderly and as our population is getting older in both the developed and the developing world, there has been an increase in the prevalence of AS. It is impacting the mortality and morbidity of our elderly population. It is also causing a huge burden on the healthcare system. There has been tremendous progress in our understanding of AS in recent years. Lately, studies have shown that AS is not just a disease of the aortic valve but it affects the entire systemic vasculature. There are studies looking at more sophisticated measures of disease severity that might better predict the optimal timing of valve replacement. The improvement in our understanding in etiology and pathophysiology of the disease process has led to a number of trials with possible treatment options for AS. In this review, we talk about our understanding of the disease and latest developments in disease assessment and management. We look forward to a time when there will be medical treatment for AS.

Thirty-day results of the SAPIEN aortic Bioprosthesis European Outcome (SOURCE) Registry: A European registry of transcatheter aortic valve implantation using the Edwards SAPIEN valve

BACKGROUND

Transcatheter aortic valve implantation was developed to mitigate the mortality and morbidity associated with high-risk traditional aortic valve replacement. The Edwards SAPIEN valve was approved for transcatheter aortic valve implantation transfemoral delivery in the European Union in November 2007 and for transapical delivery in January 2008.

METHODS AND RESULTS

The SAPIEN Aortic Bioprosthesis European Outcome (SOURCE) Registry was designed to assess the initial clinical results of the Edwards SAPIEN valve in consecutive patients in Europe after commercialization. Cohort 1 consists of 1038 patients enrolled at 32 centers. Patients who were treated with the transapical approach (n=575) suffered more comorbidities than the transfemoral patients (n=463), resulting in a significantly higher logistic EuroSCORE (29.1% versus 25.7%; P<0.001). Therefore, these groups are considered different, and outcomes cannot be compared. Overall short-term procedural success was observed in 93.8%. The incidence of valve embolization was 0.3% (n=3), and coronary obstruction was reported for 0.6% (n=6 cases). Incidence of stroke was 2.5% and similar for both procedural approaches. Thirty-day mortality was 6.3% in transfemoral patients and 10.3% in transapical patients. The occurrence of vascular complications was not a predictor of <30-day mortality in the transfemoral population.

CONCLUSIONS

Technical proficiency can be learned and adapted readily as demonstrated by the short-term procedural success rate and low 30-day mortality rates reported in the SOURCE Registry. Specific complication management and refinement of patient selection are needed to further improve outcomes.

Transcatheter aortic valve implantation: the state of play

Aortic stenosis is the most commonly acquired valvular heart disease in the Western world. Surgical aortic valve replacement is currently the gold-standard treatment for patients with severe symptomatic aortic stenosis. Without surgery, the prognosis is extremely poor, with a 3-year survival rate of less than 30%. Transcatheter aortic valve implantation (TAVI) is a rapidly evolving novel technique that was first introduced in 2002 and is currently available in Europe as an alternative to conventional aortic valve replacement for patients with severe symptomatic aortic stenosis who are deemed to be at too high a risk for open heart surgery. This article describes the TAVI technique and patient selection criteria. We explore how far we have come with advances in TAVI and analyze the short- and medium-term outcome data reported on TAVI so far. We will also look at the potential future role of TAVI and the challenges involved in setting up a TAVI service.

Immediate and mid-term results of transfemoral aortic valve implantation using either the Edwards Sapien transcatheter heart valve or the Medtronic CoreValve System in high-risk patients with aortic stenosis

OBJECTIVE

We sought to describe the results of transfemoral aortic valve implantation using either the Sapien prosthesis or the CoreValve System.

BACKGROUND

Results of transfemoral aortic valve implantation using both commercially available prostheses have rarely been studied.

PATIENTS

Of 236 patients at high-risk or with contraindications to surgery, consecutively referred for transcatheter aortic valve implantation between October 2006 and June 2009, 83 were treated with transfemoral aortic valve implantation. The Sapien was the only prosthesis available until May 2008 and, since then, was used as the first option, while the CoreValve System was used when contraindications to the Sapien prosthesis were present.

RESULTS

Patients were aged 81+/-9 years, 98% in New York Heart Association classes III/IV, with predicted surgical mortalities of 26+/-14% using the EuroSCORE and 15+/-8% using the Society of Thoracic Surgeons Predicted Risk of Mortality score. Seventy-two patients were treated with the Sapien prosthesis and 11 with the CoreValve System. The valve was implanted in 94% of the cases. Thirty-day mortality was 7%. Overall, 1- and 2-year survival rates were 78+/-5% and 71+/-7%, respectively. Among patients treated with the Sapien, the 1-year survival rate was 67+/-12% in the first 20% of patients versus 86+/-5% in the last 80% of patients (p=0.02). In univariate analysis, early experience was the only significant predictor of 1-year mortality.

CONCLUSION

Combining the use of the Sapien and the CoreValve prostheses increases the number of patients who can be treated by transfemoral aortic valve implantation and provides satisfactory results at 2 years in this high-risk population. The results are strongly influenced by experience.

Transcatheter aortic valve replacement: a dog bone-shaped balloon technique

We report a new technique of the partially and sequentially gonflage of the transcatheter balloon valve, the so called dog bone shaped technique, which allowed us to approach the aortic root by inflating the valve balloon in two different times, stabilizing the heart and deplacing the valve.

The future of new aortic valve replacement approaches

Aortic valve disease is a growing cause of mortality and morbidity, especially in developed countries. Whereas medical therapy is associated with an ominous prognosis, since the 1970s, surgical valve replacement has represented a standard therapy for fit patients. Indeed, this approach is safe and feasible in younger patients without comorbidities. However, in unfit patients, surgery may be associated with a very high risk. The advent of transcatheter valve replacement techniques, by means of percutaneous or transapical approaches, has been recently introduced into mainstream clinical practice and is likely to radically change the treatment of aortic valve disease. At present, further data are needed to thoroughly appraise the long-term risk–benefit balance of transcatheter valve replacement techniques. For this reason, it can only be considered for high surgical risk patients, but early results are so promising that in the future, transcatheter aortic valve implantation could became the first therapeutic choice, even for low-risk patients.

Transcatheter aortic valve implantation: role of multimodality cardiac imaging

Current evidence based on more than 8000 high-risk patients with severe aortic stenosis has demonstrated that transcatheter aortic valve implantation (TAVI) is a feasible alternative to surgical aortic valve replacement in selected patients. Despite current promising results on hemodynamic and clinical improvements, there are several unresolved safety issues, such as the frequency of vascular complications, postprocedural paravalvular leak, atrioventricular heart block and stroke. Multimodality cardiac imaging may help to minimize these complications and may play a central role before (optimizing patient selection, selection of appropriate prosthesis size and anticipating the procedural approach), during and after TAVI (evaluating the immediate and long-term procedural results). This article reviews the state-of-the-art TAVI procedures and the role that multimodality cardiac imaging plays before, during and after TAVI.

Absence of prosthesis-patient mismatch with the new generation of Edwards stented aortic bioprosthesis

Prosthesis-patient mismatch (PPM) remains a controversial issue with the most recent stented biological valves. We analyzed the incidence of PPM after implantation of the Carpentier-Edwards Perimount Magna Ease aortic valve (PMEAV) bioprosthesis and assessed the early clinical outcome. Two hundred and seventy consecutive patients who received a PMEAV bioprosthesis between January 2007 and July 2008 were analyzed. Pre-, peri- and postoperative data were assessed and echocardiographic as well as clinical follow-up was performed. Mean age was 72+/-9 years, 168 (62.2%) were males. Fifty-seven patients (21.1%) were below 65 years of age. Absence of PPM, corresponding to an indexed effective orifice area >0.85 cm(2)/m(2), was 99.5%. Observed in-hospital mortality was 2.2% (six patients), with a predicted mortality according to the additive EuroSCORE of 7.6+/-3.1%. At echocardiographic assessment after a mean follow-up period of 150+/-91 days, mean transvalvular gradient was 11.8+/-4.8 mmHg (all valve sizes). No paravalvular leakage was seen. Nine patients died during follow-up. The Carpentier-Edwards PMEAV bioprosthesis shows excellent hemodynamic performance. This valve can be implanted in all sizes with an incidence of severe PPM below 0.5%.

The utility of trans-catheter aortic valve replacement after commercialization: does the European experience provide a glimpse into the future use of this technology in the United States?

Treatment of aortic stenosis remains challenging in older individuals, as their perioperative mortality for open heart surgery is increased due to comorbidities. Transcatheter aortic valve implantation using the CoreValve ReValving System (Medtronic, Minneapolis, USA) and the Edwards SAPIEN transcatheter heart valve (THV; Edwards Lifescience, Irvine, California, USA) represents an alternative to conventional valve replacement in elderly patients that have a high risk for conventional surgery. This article summarizes the evidence-base from recent clinical trials. The early results of these landmark studies suggest that transcatheter aortic valve implantation with either one of the prosthesis is feasible, safe, improves hemodynamics and, therefore, might be an alternative to conventional aortic valve replacement in very high-risk patients. However, all of the available transcatheter heart valves have certain disadvantages, limiting their use in daily clinical practice. The process of decision making, which valve to use and which access route to choose is illustrated in this article through clinical case scenarios. Additionally, the lessons learned thus far from the European perspective and the potential impact on the future use in the US are discussed. Despite of the progress in this field, we are still lacking an optimal transcatheter heart valve. Once it is available, we can take the plunge to compare transcatheter valve implantation with convention surgery in severe aortic stenosis!

Risk and fate of cerebral embolism after transfemoral aortic valve implantation: a prospective pilot study with diffusion-weighted magnetic resonance imaging

OBJECTIVES

The aim of this study was prospective investigation of silent and clinically apparent cerebral embolic events and neurological impairment after transfemoral aortic valve implantation (TAVI).

BACKGROUND

TAVI is a novel therapeutic approach for multimorbid patients with severe aortic stenosis. We investigated peri-interventional cerebral embolism with diffusion-weighted magnetic resonance imaging (DW-MRI) and its relationship to clinical and serologic parameters of brain injury.

METHODS

Cerebral DW-MRI was performed before, directly, and 3 months after TAVI with the current third-generation self-expanding CoreValve (Medtronic, Minneapolis, Minnesota) prosthesis. At the timepoints of the serial MRI studies, focal neurological impairment was assessed according to the National Institutes of Health Stroke Scale (NIHSS), and serum concentration of neuron-specific enolase (NSE), a marker of the volume of brain tissue involved in an ischemic event, were determined.

RESULTS

Thirty patients were enrolled; 22 completed the imaging protocol. Three patients (10%) had new neurological findings after TAVI, of whom only 1 (3.6%) had a permanent neurological impairment. Of the 22 TAVI patients with complete imaging data, 16 (72.7%) had 75 new cerebral lesions after TAVI presumed to be embolic. The NIHSS and NSE were not correlated with DW-MRI lesions.

CONCLUSIONS

The incidence of clinically silent peri-interventional cerebral embolic lesions after TAVI is high. However, in this cohort of 30 patients, the incidence of persistent neurological impairment was low. (Incidence and Severity of Silent and Apparent Cerebral Embolism After Conventional and Minimal-invasive Transfemoral Aortic Valve Replacement; NCT00883285).

Current role and outcomes of ascending aortic replacement for severe nonaneurysmal aortic atherosclerosis

BACKGROUND

Severe atherosclerosis of the ascending aorta is a challenging issue potentially affecting indications for surgery, operative choices, and patients' outcome. No standard treatment has emerged to date, and uncertainties persist about criteria for selecting patients and procedures.

METHODS

Replacement of the atherosclerotic ascending aorta was performed in 64 patients at time of either aortic (n = 49), mitral (n = 21), or tricuspid (n = 7) valve surgery. Coronary artery bypass grafting was performed in 53 patients, and the majority of patients underwent combined procedures (n = 49). Mean age was 72.0 +/- 7.6 years. The expected operative mortality, by logistic European System for Cardiac Operative Risk Evaluation, was 29.0% accounting for ascending aortic replacement and 13.1% disregarding it. Circulatory arrest under deep hypothermia, eventually combined with either retrograde or antegrade brain perfusion, was required in 61 cases.

RESULTS

Early death, stroke, and myocardial infarction rates were 10.9%, 6.3%, and 7.8%, respectively. Factors univariately associated with early deaths were preoperative renal failure requiring dialysis (p = 0.001) and longer cardiopulmonary bypass (p = 0.001) and cardioplegia (p = 0.008) times. Cumulative survival at 1, 3, and 5 years was 86% +/- 4%, 74% +/- 6%, and 68% +/- 8%, respectively.

CONCLUSIONS

Replacement of the atherosclerotic ascending aorta can be carried out at acceptable mortality rates despite the high rates of preoperative comorbidity and the significant incidence of postoperative complications.

Transcatheter aortic valve implantation for the treatment of severe symptomatic aortic stenosis in patients at very high or prohibitive surgical risk: acute and late outcomes of the multicenter Canadian experience

OBJECTIVES

The aim of this study was: 1) to evaluate the acute and late outcomes of a transcatheter aortic valve implantation (TAVI) program including both the transfemoral (TF) and transapical (TA) approaches; and 2) to determine the results of TAVI in patients deemed inoperable because of either porcelain aorta or frailty.

BACKGROUND

Very few data exist on the results of a comprehensive TAVI program including both TA and TF approaches for the treatment of severe aortic stenosis in patients at very high or prohibitive surgical risk.

METHODS

Consecutive patients who underwent TAVI with the Edwards valve (Edwards Lifesciences, Inc., Irvine, California) between January 2005 and June 2009 in 6 Canadian centers were included.

RESULTS

A total of 345 procedures (TF: 168, TA: 177) were performed in 339 patients. The predicted surgical mortality (Society of Thoracic Surgeons risk score) was 9.8 +/- 6.4%. The procedural success rate was 93.3%, and 30-day mortality was 10.4% (TF: 9.5%, TA: 11.3%). After a median follow-up of 8 months (25th to 75th interquartile range: 3 to 14 months) the mortality rate was 22.1%. The predictors of cumulative late mortality were peri-procedural sepsis (hazard ratio [HR]: 3.49, 95% confidence interval [CI]: 1.48 to 8.28) or need for hemodynamic support (HR: 2.58, 95% CI: 1.11 to 6), pulmonary hypertension (PH) (HR: 1.88, 95% CI: 1.17 to 3), chronic kidney disease (CKD) (HR: 2.30, 95% CI: 1.38 to 3.84), and chronic obstructive pulmonary disease (COPD) (HR: 1.75, 95% CI: 1.09 to 2.83). Patients with either porcelain aorta (18%) or frailty (25%) exhibited acute outcomes similar to the rest of the study population, and porcelain aorta patients tended to have a better survival rate at 1-year follow-up.

CONCLUSIONS

A TAVI program including both TF and TA approaches was associated with comparable mortality as predicted by surgical risk calculators for the treatment of patients at very high or prohibitive surgical risk, including porcelain aorta and frail patients. Baseline (PH, COPD, CKD) and peri-procedural (hemodynamic support, sepsis) factors but not the approach determined worse outcomes.

Transcatheter aortic valve implantation: what has been done and what is going to be done

Transcatheter valve implantation is developing into an effective and reproducible therapy for aortic valve stenosis. The origin of this technique was pursued in 1992 when Andersen demonstrated the feasibility of percutaneous implantation of catheter-based valve prosthesis. Since then a lot of technical and device advances have been made and to date, transcatheter aortic valve implantation has became a concrete alternative to surgical replacement. This paper aims to go over all the current devices, from the most widely used to the newest technology, focusing on device description, procedural issues, potential complications and clinical studies currently available in literature.